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Forecasts of cosmological constraints from HI intensity mapping with FAST,BINgO and SKA-I

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Research in Astronomy and Astrophysics 2019年第12期19卷 343-360页

作者： Elimboto Yohana yi-Chao Li yin-Zhe Ma Astrophysics and Cosmology Research Unit School of MathematicsStatistics&Computer ScienceUniversity of KwaZulu-NatalWestville CampusPrivate Bag X54001Durban4000South Africa Dar Es Salaam University College of Education A Constituent College of the University of Dar Es SalaamP.O.Box 2329 Dar Es SalaamTanzania Astrophysics and Cosmology Research Unit School of Chemistry and PhysicsUniversity of KwaZulu-NatalWestville CampusPrivate Bag X54001Durban4000South Africa NAOC-UKZN Computational Astrophysics Centre(NUCAC) University of KwaZulu-NatalDurban4000South Africa

We forecast the cosmological constraints of the neutral hydrogen(HI) intensity mapping(IM)technique with radio telescopes by assuming 1-year of observational time. The current and future radio telescopes that we consider here are Five-hundred-meter Aperture Spherical radio Telescope(FAST), Baryon acoustic oscillations In Neutral gas Observations(BINgO), and Square Kilometre Array phase Ⅰ(SKA-Ⅰ) single-dish experiments. We also forecast the combined constraints of the three radio telescopes with Planck. We find that the 1σ errors of(w0, wa) for BINgO, FAST and SKA-Ⅰ with respect to the fiducial values are respectively,(0.9293, 3.5792),(0.4083, 1.5878) and(0.3158, 0.4622). This is equivalent to(56.04%, 55.64%) and(66.02%, 87.09%) improvements in constraining(w0, wa) for FAST and SKA-Ⅰ respectively relative to BINgO. Simulations further show that SKA-Ⅰ will put more stringent constraints than both FAST and BINgO when each of the experiments is combined with Planck measurements. The 1σ errors for(w0, wa), BINgO + Planck, FAST + Planck and SKA-Ⅰ + Planck covariance matrices are respectively(0.0832, 0.3520),(0.0791, 0.3313) and(0.0678, 0.2679) implying there is an improvement in(w0, wa) constraints of(4.93%, 5.88%) for FAST + Planck relative to BINgO + Planck and an improvement of(18.51%, 23.89%) in constraining(w0, wa) for SKA-Ⅰ + Planck relative to BINgO + Planck. We also compared the performance of Planck data plus each single-dish experiment relative to Planck alone,and find that the reduction in(w0, wa) 1σ errors for each experiment plus Planck, respectively, imply the(w0, wa) constraints improvement of(22.96%, 8.45%),(26.76%, 13.84%) and(37.22%, 30.33%) for BINgO + Planck, FAST + Planck and SKA-Ⅰ + Planck relative to Planck alone. For the nine cosmological parameters in consideration, we find that there is a trade-off between SKA-Ⅰ and FAST in constraining cosmological parameters, with each experiment being more superior in constraining a particular set of parameter

关键词： surveys galaxies:statistics cosmology:observations large-scale structure of Universe galaxies:kinematics and dynamics

Nd-Fe-B/FeCo多层纳米复合膜的结构和磁性

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物理学报 2007年第2期56卷 1135-1140页

作者：敖琪张瓦利张熠吴建生上海交通大学

制备了Nd28Fe66B6/Fe50Co50多层纳米复合磁性薄膜,对溅射态和650℃退火处理15min试样的相成分分析和微结构的观察显示,溅射态薄膜呈非晶态,经650℃退火处理15min后,薄膜主要相成分为硬磁性Nd2Fe14B相和软磁性相FeCo(110)相.Nd2Fe14B相... 详细信息

制备了Nd28Fe66B6/Fe50Co50多层纳米复合磁性薄膜,对溅射态和650℃退火处理15min试样的相成分分析和微结构的观察显示,溅射态薄膜呈非晶态,经650℃退火处理15min后,薄膜主要相成分为硬磁性Nd2Fe14B相和软磁性相FeCo(110)相.Nd2Fe14B相呈柱状,其易磁化c轴垂直于膜面,尺寸约10nm.在硬磁性相和软磁性相之间存在少量富Nd相和非晶态,富Nd相大小约7nm.磁性测量和分析表明,1)该系列薄膜退火态具有垂直于膜面的磁晶各向异性.2)对于固定厚度(10nm)层Nd-Fe-B和不同厚度(tFeCo=1—100nm)层FeCo多层纳米复合膜,剩磁随软磁相FeCo厚度的增加快速增加,而矫顽力则减小.当tFeCo=5nm时,最大磁能积达到200kJ/m3.3)硬磁相Nd-Fe-B层和软磁相FeCo层之间交换耦合导致剩磁和磁能积增强.

关键词： Nd-Fe-B/FeCo多层纳米复合膜交换耦合磁各向异性

An Efficient Bio-inspired Oxygen Reduction Reaction Catalyst:MnO_(x)Nanosheets Incorporated Iron Phthalocyanine Functionalized graphene

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Energy & Environmental Materials 2021年第3期4卷 474-480页

作者： Xing Wu yi Cheng Jean-Pierre Veder San Ping Jiang Department of Environmental Engineering School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083China National Engineering Technology Research Center for Control and Treatment of Heavy-metal Pollution Changsha 410083China John de Laeter Centre Curtin UniversityPerth WA 6102Australia Fuels and Energy Technology Institute Curtin UniversityPerth WA 6102Australia

Oxygen reduction reaction(ORR)catalysts play a critical role in energy storage and conversion devices and have been attracted enormous interests,and however,it remains challenging to develop highly active cheap catalysts in a simple and green *** by the heme-copper oxidases(HOCs),in which the ORR active center is originated from the incorporation of Fe-N_(4)with copper atom,we here developed a fine manganese oxide nanosheets(MnO_(x)NSs)integrated with iron phthalocyanine(FePc)anchored on highly conductive graphene(MnO_(x)/FePc-g)through a green route only involve ethanol as the *** bio-inspired catalyst MnO_(x)/Fe Pc-g demonstrated high ORR activity with a half-wave potential(E_(1/2))of 0.887 V,about 57 mV more positive than that of Pt/*** the current density(j)at 0.9 V is about 1.9 m A cm^(-2),which is three times of Pt/C and *** importantly,the bio-inspired systems show superior stability in comparison to commercial Pt/C,showing a potential of 0.863 V to deliver a j of 3 mA cm^(-2)after 18000 s polarization,about 80 mV higher than that of 0.783 V for Pt/*** high activity is contributed by the integration of the Fe Pc and MnO_(x)NSs that plays the role to assist the cleavage of the O_(2)*** approach provides a new evidence to develop highly efficient ORR catalysts through imitate the naturally involved systems through a simple route.

关键词： bio-inspired heme-copper oxidases iron phthalocyanine MnO_(x)nanosheets oxygen reduction reaction

利用分布式狼群算法进行三维传感器优化布置的方法研究

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振动工程学报 2014年第5期27卷 668-675页

作者：伊廷华王传伟李宏男大连理工大学建设工程学部土木工程学院辽宁大连116023

考虑传感器优化布置中的模态置信准则MAC只能对三维传感器的某一方向进行优化,而不能确保在三个方向同时实现优化布置的问题,提出将节点的三个平动自由度作为一个单元,通过节点的Fisher信息阵来获取结构所布置传感器的Fisher信息阵,并... 详细信息

考虑传感器优化布置中的模态置信准则MAC只能对三维传感器的某一方向进行优化,而不能确保在三个方向同时实现优化布置的问题,提出将节点的三个平动自由度作为一个单元,通过节点的Fisher信息阵来获取结构所布置传感器的Fisher信息阵,并借鉴传统一维模态置信准则的思想,构建了一种全新的三维模态置信准则TMAC。为提高算法的求解效率,提出了一种分布式狼群算法,采用双重编码方式,克服原狼群算法只能求解连续变量优化的问题;采用狼群分组的方法,通过组内狼个体的信息交流,提高了算法的搜索效率。文末以中佛罗里达大学建立的基准模型为例,进行了参数敏感性分析以及三维传感器优化布置方案的选择,结果表明:分布式狼群算法的搜索能力较原狼群算法有了大幅提高,能较好地解决传感器优化布置问题。

关键词：传感器优化布置模态置信准则狼群算法双重编码基准模型

Nd_(28)Fe_(66)B_6/Fe_(50)Co_(50)双层纳米复合膜的结构和磁性

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物理学报 2005年第10期54卷 4889-4893页

作者：敖琪张瓦利张熠吴建生上海交通大学高温材料与高温测试教育部重点实验室上海200030

利用磁控溅射法制备了Nd28Fe66B6/Fe50Co50双层纳米复合磁性薄膜,研究了其结构和磁性.经873K退火处理15min后,利用x射线衍射仪测定薄膜晶体结构,采用俄歇电子能谱仪估算薄膜厚度和超导量子干涉仪测量其磁性.磁性测量表明,1)该系列薄膜... 详细信息

利用磁控溅射法制备了Nd28Fe66B6/Fe50Co50双层纳米复合磁性薄膜,研究了其结构和磁性.经873K退火处理15min后,利用x射线衍射仪测定薄膜晶体结构,采用俄歇电子能谱仪估算薄膜厚度和超导量子干涉仪测量其磁性.磁性测量表明,1)该系列薄膜具有垂直于膜面的磁各向异性.从起始磁化曲线和小回线的形状特征可知,矫顽力机制主要是由畴壁钉扎控制.2)对于固定厚度(10nm)层的硬磁相Nd-Fe-B和不同厚度(dFeCo=1—100nm)层软磁相FeCo双层纳米复合膜,剩磁随软磁相FeCo厚度的增加快速增加,而矫顽力则减少.当dFeCo=5nm时,最大磁能积达到160×103A/m.磁滞回线的单一硬磁相特征说明,硬磁相Nd-Fe-B层和软磁相FeCo层之间的相互作用使两相很好地耦合在一起.剩磁和磁能积的提高是由于两相磁性交换耦合所致.

关键词： Nd-Fe-B/FeCo双层纳米复合膜交换耦合磁性增强纳米复合膜磁性薄膜晶体结构 Nd-Fe-B 超导量子干涉仪俄歇电子能谱仪矫顽力机制

Log-rank and stratified log-rank tests

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Statistical Theory and Related Fields 2023年第4期7卷 309-317页

作者： Ting Ye Jun Shao Yanyao yi Department of Biostatistics University of WashingtonSeattleWAUSA School of Statistics East China Normal UniversityShanghaiPeople’s Republic of China Department of Statistics University of WisconsinMadisonWIUSA global Statistical Sciences Eli Lilly and CompanyIndianapolisINUSA

In randomized clinical trials with right-censored time-to-event outcomes,the popular log-rank test without adjusting for baseline covariates is asymptotically valid for treatment effect under simple randomization of treatments but is too conservative under covariate-adaptive *** stratified log-rank test,which adjusts baseline covariates in the test procedure by stratification,is asymptotically valid regardless of what treatment randomization is *** the literature,however,under simple randomization there is no affirmative conclusion about whether the stratified log-rank test is asymptotically more powerful than the unstratified log-rank *** this article we show when the stratified and unstratified log-rank tests aim for the same null hypothesis and that,under simple randomization,the stratified log-rank test is asymp-totically more powerful than the unstratified log-rank test in the region of alternative hypothesis that is specified by a Cox proportional hazards *** also provide some discussion about why we do not have an affirmative conclusion in general.

关键词： Baseline covariates covariate-adaptive randomization null hypothesis of no treatment eﬀect Pitman’s relative effciency time-to-event validity of tests

Quantitative and qualitative changes in serum luteinizing hormone after injectable testosterone undecanoate treatment in hypogonadal men

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Asian Journal of Andrology 2000年第1期2卷 65-71页

作者： yi-QungU Zheng-YangE gui-YuanZHANg WilliamJ.Bremner NationalResearchInstituteforFamilyPlanning Beijing100081China Xi-YuanHospital AffiliatedtoChineseAcademyofTraditionalChineseMedicineBeijing100091China PopulationCenterforResearchinReproduction.DepartmentofMedicine.Universityofwashington SeattleWA98195U.S.A.

Aim: To clarify the immuno-active LH (i-LH) and bioactive LH (b-LH) responses and qualitative changes in the cir-culating LH to testosterone undecanoate (TU) injection. Methods: Eight men with Klinefelter's syndrome were re-cruited for the study. They received crossover injections of TU at doses of 500 and 1000 mg. Serum i-LH and b-LHlevels before and at various time intervals after TU injection were measured and the serum i-LH, b-LH, b-LH/i-LH(B/I) and testosterone/sex hormone-binding globulin (T/SHBg) ratio in LH-responders and LH non-responders werecompared. Results: A parallel suppression of serum i-LH and b-LH was consistent with their overall high correlationbetween each other ( r = 0.84, P gher E_2 levels and T/SHBg ratio. There was a quantitative change in serum LH as induced by TU without qualitative change within LH-re-sponders os LH-non-responders. Conclusion: A high loading dose (1000 mg) of TU is important for the initial sup-pression of LH. With the lower dose (500 mg), repeated injections will be required to attain such LH suppression forthe purpose of fertility regulation. The lower baseline serum i-LH level may be an intrinsic characteristic of LH-respon-ders.

关键词： LH bioactivity testosterone estrogen

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茜素红与头孢哌酮的荷移反应研究与应用

分析试验室 2011年第1期30卷 48-50页

作者：敖登高娃邢高娃刘俊轶内蒙古大学化学化工学院呼和浩特010021

实验以茜素红(ARS)为荷移试剂,采用分光光度法研究了ARS与头孢哌酮(CPZ)形成络合物的光谱性质及其反应的适宜条件。实验结果表明:头孢哌酮在2.0～200μg/mL范围内遵循比尔定律,回归方程为:A=0.0036ρ+0.000095(:ρμg/mL),检出限0.75μg... 详细信息

实验以茜素红(ARS)为荷移试剂,采用分光光度法研究了ARS与头孢哌酮(CPZ)形成络合物的光谱性质及其反应的适宜条件。实验结果表明:头孢哌酮在2.0～200μg/mL范围内遵循比尔定律,回归方程为:A=0.0036ρ+0.000095(:ρμg/mL),检出限0.75μg/mL,表观摩尔吸光系数2.64×104L·mol-1·cm-1,相关系数为r=0.9965,并初步探讨了反应机理。用实验方法对尿样及生物样品进行加标回收测定,回收率在95.4%～104.8%。

关键词：茜素红头孢哌酮分光光度法

5′-硝基-水杨基荧光酮与头孢哌酮的显色反应

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分析试验室 2010年第9期29卷 32-34页

作者：邢高娃敖登高娃刘俊轶内蒙古大学化学化工学院呼和浩特010021

采用分光光度法,以5′-硝基-水杨基荧光酮(5′-NSAF)为显色剂,研究了5′-NSAF与头孢哌酮(CPZ)的络合物的可见光谱性质及反应条件。实验结果表明:头孢哌酮在6.68~133.6μg/mL范围内遵循比尔定律,回归方程为:A=0.0031ρ+0.023(ρ:μg/mL)... 详细信息

采用分光光度法,以5′-硝基-水杨基荧光酮(5′-NSAF)为显色剂,研究了5′-NSAF与头孢哌酮(CPZ)的络合物的可见光谱性质及反应条件。实验结果表明:头孢哌酮在6.68~133.6μg/mL范围内遵循比尔定律,回归方程为:A=0.0031ρ+0.023(ρ:μg/mL),检出限6.27μg/mL,表观摩尔吸光系数1.89×***-1,相关系数为r=0.9970,并探讨了其反应机理。方法已用于尿样及生物样品中头孢哌酮含量的测定。

关键词： 5′-硝基-水杨基荧光酮头孢哌酮分光光度法